A novel approach for enhancement of atomic spin polarization in spin-exchange relaxation-free gyroscopes based on a homogenized light field

Atomic spin comagnetometers based on the spin-exchange relaxation-free (SERF) effect offer significant potential for inertial sensing and support the development of long-endurance, high-precision navigation technologies. However, limited nuclear spin polarization constrains the long-term stability of these systems. Here, a flat-top optical pumping configuration is introduced for SERF comagnetometers, expanding the uniform-intensity region of the beam to approximately 62%, which enhances atomic polarization by around 19% and improves magnetic noise suppression by 32%. Experimental results demonstrate notable improvements in both sensitivity and long-term stability, highlighting the effectiveness of flat-top beams in overcoming atomic polarization uniformity limitations and advancing SERF co-magnetometer performance.